Climate Overview
The climate in San José is hot. The average annual temperature is 27°C and approximately 1273mm of precipitation falls per year. September is the wettest month, receiving around 239mm of rainfall. San José is in the Northern Hemisphere. Summer begins at the end of June and lasts through September. The summer months are: May, April, March. The coldest months are January, February, December, when temperatures can drop to 20°C.
Temperature
San José sees moderate temperature variation throughout the year, ranging from 20°C to 39°C. May is the hottest month, with daytime highs reaching 39°C and an average of 31°C. January is the coolest month, with minimum temperatures around 20°C and an average of 24°C. On average, daily temperatures fluctuate by about 11°C between overnight lows and afternoon highs. The sharpest temperature change occurs between February and March, with a 3°C shift in average temperatures.
Precipitation
San José is a fairly wet location, receiving approximately 1273mm of precipitation annually, which averages out to around 106mm per month. The wettest month is September, averaging 239mm of rainfall. June and October also tend to see above-average precipitation. The driest month is February, with just 22mm. That's 217mm less than September, the wettest month. Rainfall is heavily concentrated in certain months, creating a distinct wet and dry season. Visitors should plan around these patterns, as the difference between peak and low months is dramatic.
Wind
San José is relatively calm, with an average annual wind speed of 7km/h. For context, sustained winds below 12km/h are generally light, while anything above 25km/h is considered strong. The windiest month is April, averaging 9km/h, though still comfortable for most outdoor activities. The calmest conditions occur in September, with average winds dropping to 5km/h, making it an ideal period for wind-sensitive activities. There is moderate seasonal variation in wind speed, with a 4km/h gap between the calmest and windiest months.
Seasons
87 days until Winter
It is currently autumn in San José, which began on September 23, 2026. San José is in the Northern Hemisphere, where spring begins in March, summer in June, autumn in September, and winter in December. The warmest period peaks in May at around 39°C, while the coldest stretch bottoms out in January near 20°C. Winter is next, beginning on December 21, 2026 (87 days from now).
Spring
Temperatures range from 22 to 39°C. Rainfall is relatively light, with around 122mm over the season and a monthly average of 41mm. Winds are generally light, averaging 8km/h. Light layers work well as temperatures warm through the season. It is a great time to be outdoors.
Summer
Temperatures range from 24 to 35°C. Rainfall is heavy, totalling around 519mm across the season with a monthly average of 173mm. Winds are generally light, averaging 6km/h. Light, breathable clothing is ideal. Perfect conditions for outdoor activities.
Autumn
Temperatures range from 21 to 33°C. Rainfall is heavy, totalling around 520mm across the season with a monthly average of 173mm. Winds are generally light, averaging 6km/h. A waterproof jacket and sturdy footwear are recommended as rain becomes more frequent.
Winter
Temperatures range from 20 to 32°C. Rainfall is relatively light, with around 112mm over the season and a monthly average of 37mm. Winds are generally light, averaging 7km/h. A light jacket or sweater is usually sufficient, though cooler evenings may call for an extra layer.
Best Time to Visit
The best time to visit San José is during January and December, when the weather is most comfortable for travellers. During these months, average temperatures hover around 24°C with modest rainfall averaging 45mm per month. By contrast, May can be uncomfortably hot with temperatures reaching 39°C. A light rain jacket is recommended, though showers are generally brief and shouldn't disrupt your plans.
Monthly Climate Data
The table below shows monthly climate averages for San José based on historical weather data. Min and max temperatures represent typical overnight lows and afternoon highs for each month, shown in degrees Celsius (°C). Precipitation is measured in millimetres (mm) and indicates the average total rainfall per month. Wind speed is the average sustained speed in kilometres per hour (km/h). All values are based on averages from over 10 years of historical weather data. The current month is highlighted for quick reference.
